The Giscome Rapids deposit is located on the west bank of the Fraser River near the foot of Giscome Rapids. In 1942, an area about 30 metres square on the river bank was stripped and 18 tonnes of clay was mined and shipped to Vancouver. In 1947, several holes were drilled by hand auger.

The deposit consists of good stoneware-china clay with up to cone 31 softening points and cream to white burning. The clay occurs in a Tertiary bed, at least 9 metres thick and 90 metres wide, exposed for about 0.8 kilometre along the river bank. The clay comprises a variety of different clays starting with a surface type (A) and ending with a darker brown clay (G). The clays in between (B to E) are classed as good white open firing clays of refractory grade, suitable for whitewares and refractories. These clays range from light-grey through blue-grey to brown in color. The material removed was surface clay

Samples of all the clays from the 1947 drill holes were found to have good plasticity, despite containing 20 to 45 per cent silica sand, and drying behavior was satisfactory. The extent of the large deposit has not been proven but high-grade clay is available.

Sampling of the Tertiary clays in 1996 for Darren Resources Limited was initiated to acquire preliminary indications as to their suitability for processing into filter and coater grade kaolin. Five samples from the lower and upper lower levels of clay were collected. The high silica content and low brightness of these clay samples indicate them to be unsuitable for use as paper fillers or coaters. The cause of the low brightness was to be identified.